Intake valves

With the intake valve open, the piston movement to the right creates a low pressure region in the cylinder, which causes air and fuel to flow through the intake valve to fill the cylinder. 

The intake valve is now closed as the piston moves from the bottom dead center (BDC) to top dead center (TDC), compressing the fuel/air mixture. At Point 3, just prior to TDC, a spark ignites the fuel/air mixture and the resulting combustion causes the pressure and temperature to begin a very rapid rise within the cylinder. 

Intake Manifold Valve Guide Intake Valve... 

The power that can be produced in each cylinder depends on the amount of air it can induct. Recent interest in replacing the traditional single-intake valve per cylinder with two smaller ones, and in a tew cases even three, has increased total intake-valve area, and hence engine airflow at a given speed. At the same time, engine speed capability has been increased. 

The four-stroke engine requires four piston strokes (or two crankshaft revolutions) for each cycle. In a downward stroke, the intake valve is opened and the combustible mixture is brought into the cylinder. In an upward stroke the fuel-air mixture is compressed and ignited near the top of the stroke. This forces the piston downward (to provide power). In the next upward stroke the exhaust valve is opened and the spent gases are forced from the cylinder. In the following downward stroke, the cycle is repeated with the opening of the intake valve. 

Between Points 1 and 2 in Figure B.2, the intake and discharge valves are closed and the gas in the cylinder is compressed from Px to P2. When the pressure reaches P2, the discharge valve opens and the gas is pushed from the cylinder between Points 2 and 3 in Figure B.2. Between Points 3 and 4, the intake and discharge valves are closed and any gas remaining in the cylinder is expanded to the intake pressure of Pi. Between Points 4 and 1, the intake valve opens and the suction stroke draws gas into the cylinder at pressure Pi. The total work for the cycle is the sum of the work for the four steps. The work required by the compression is often termed shaft work Ws. Thus ... 

Premature ignition can be reduced or eliminated by redesigning the fuel delivery system, which can be categorized into three types central-, port-, and direct injection. Central and port fuel injections form the fuel-air mixture during the intake stroke. In the case of central injection (or a carburetor), the injection is at the inlet of the air intake manifold. In the case of port injection, fuel is injected at the inlet port. Direct injection is technologically sophisticated and involves forming the fuel-air mixture inside the combustion cylinder after the air intake valve has closed [27-36]. 

Insulin permeation rate, 9 69 Intake valve deposits (IVD), 12 409—410 Intake valve detergents, 12 409 Intalox saddles, 1 28 8 770... 

A four-stroke Miller-Otto cycle without supercharger and intercooler is shown in Fig. 3.33. The intake valve is closed late at state 3. 

Variable valve timing is being developed to improve the performance and reduce the pollution emissions from internal combustion heat engines for automobiles and trucks. A unique benefit for these engines is that changing the timing of the intake valves can be used to control the... 

Determine the temperature at the end of the eompression proeess, compression work, expansion work, and thermal efficiency of an Otto Miller cycle. The volumes of the cylinder before and after compression are 3 liters and 0.3 liter. Heat added to the air in the combustion chamber is 800kJ/kg. A supercharger and an intercooler are used. The supercharger pressure is 180 kPa and the temperature at the end of the intercooler is 20°C. The intake valve closes at 2.8 liters. The end temperature of the cooling process of the cycle is 20°C. What is the mass of air in the cylinder The atmosphere conditions are 101.3 kPa and 20° C. 

These values predict the tendency of stored gasoline to form undesirable oxidation products and residue. Gums and residue may deposit on engine parts such as the intake manifold, intake valves, and intake port. Poor engine performance may result. 

Detergents/deposit control additives Help prevent deposit buildup on fuel system parts such as carburetors, fuel injectors, intake valves, valve seats, and valve guides some additives will remove existing deposits... 

---